Easy Problem

Using Arduino Programming Questions
1

Hello,

I bought Arduino Mega 2560 card, and I have a problem when I want to do flash a LED, the LED doesn't flash, it doesn't work.
The code:

int ledPin = 51;

void setup()
{
pinMode(ledPin, OUTPUT);
}

void loop()
{
digitalWrite(ledPin, HIGH);
delay(1000);
digitalWrite(ledPin, LOW);
delay(1000);
}

Thanks for yours answers :wink:

2

and I have a problem when I want to do flash a LED.

But you are not going to tell us what that problem actually is.

There is nothing wrong with that code, so it must be your wiring.

3

He sounds like he's incredibly new. My betting is either:

  • He didn't put a resistor in series with the LED, and LED is now burned out
  • LED is backwards - LEDs are polarized, and if connected backwards, they won't light.
  • Connections are loose.
4

This isn't a problem of connections or LED because I tested it with a 5V cell, and it worked.

5

AlexandreCool:
This isn't a problem of connections or LED because I tested it with a 5V cell, and it worked.

But you still don't say what the problem is. That seems like pretty important information if you want help with it.

6

The problem is that nothing happen when I start the programm (this one has been well transfer)

7

Is the LED connected the right way around?

When you tested it with 5v, did you have a resistor in series with it? Do you have one in series with it now? Using an LED without a series resistor can easily burn out an LED. I had one fail get trashed because of noise on the voltage adjust knob of the power supply as I was slowly cranking the voltage up... I had it at the right voltage, but as I removed my hand, it edged up 0.1v and the LED got real bright for a split second and then failed.

Are the connections secure? Try wiggling the wires, make sure they're not loose. Sometimes cheap clone arduinos and cheap crappy male dupont jumpers don't make a reliable connection.